Electric iron with synchronous heat indication



P 1948. c. H. SPARKLIN 2,439,825

ELECTRIC IRON WITH SYNCHRCNOUS HEAT INDICATION Filed May 13, 1944 2 Sheets-Sheet 1 April 20, 1948. c. H. SPARKLIN 2,439,825

ELECTRIC IRON WITH SYNHRONOUS HEAT INDICATION Filed May 13, 1944 2 Sheets-Sheet 2 Patented s. 20, 194s ELECTRIC mon wI'rn smonnonous HEAT INDICATION Charles Sparklin, Chicago, 111., alsignor to Birtman Electric Company, a corporation of Illinois Application May 13, 1944, Serial'No. 535,429

3 Claims. (CI. 38-74) This invention relates to a heat regulating iron and more particularly to an electric sadiron in which superimposed indicating means are provided for indicating the thermostat setting and the temperature conditions of the iron.

It is common practice in more expensive irons to provide adjustable thermostatic control for the iron which maybe set for different operating conditions. For example, cotton, wool, silk, and rayon all require different temperatures of the iron for most effective ironing. It has heretofore been proposed to provide a thermostat with an adjustment which may be operated from a handle of the iron and which bears upon the handle calibrated indicia indicating each setting of the thermostat. In some instances this adjustment is mounted on the body of the iron.

Furthermore, in some irons thermometers have been employed showing the temperature conditions of the iron, but in no case has the thermostatic adjustment been positioned in a part of the iron convenient to the fingers while the indicia have been placed with an indicator in a portion of the iron more convenient to the eye; nor has any iron included superimposition of the setting indicator and the temperature indicator so that the operator may ascertain at a single glance how the actual temperature of the iron corresponds to the predetermined setting.

The invention is illustrated in the drawings, in which Figure 1 is a side elevation of the iron; Figure 2 is a plan view thereof; Figure 3 is a side elevation partly in section; Figure 4 is a sectional plan view taken along the line 4-4- in Figure 3;, Figure 5 is a detailed plan view of the temperature recording thermostat taken along the-line 5-5 in Figure 3; Figure 6 is a partial sectional elevation of the control for the setting indicator; Figure l is a sectional plan view taken along the line 'I--'I in Figure 3; and Figure 8 is a sectional view looking upward on the line 8-8 in Figure 3.

As shown in the drawings, the iron in comprises a sole plate Ii and a hood l2 which together define the body portion of the iron, a handle support IS, a handle l4 supported thereon, and a control knob IS. The usual form of snap acting thermostat i6 is provided in the body of the iron and is afllxed to the sole plate. This thermostat may be adjusted by movement of the post l1. In the preferred form of the invention this adjustment is accomplished by rotation of the control knob in the following manner. The knob l5, as shown in Figure I, has a central opening in which an internal sleeve I8 is anchored. Within this sleeve is a threaded post I9 iii which is fastened in the sole plate at its bottom and which has a head 20 secured within a plate 2| (see Figure 8) in the handle. This plate has a key opening 22 which may he slipped over the head of the post i9, after which the handle is moved forward so that the slot 23 engages the head 20.

An elongated sleeve 25 is threaded upon the post is and is provided at its top with a square head 26 and at its base with a collar 2i having a groove 28. An arm 30 which is pivotally mounted at 3! in the bracket 32 is engaged at its front end by the sides of the slot 28. The rear end of the arm 30 bears against the post ll. As a result, when the knob i5 is rotated the head 26: is correspondingly rotated, moving the sleeve 25 and the collar 2'! upwardly or downwardly on the post Hi. When the knob is turned in a clockwise direction, as shown in Figure '7, the thermostat setting is raised, and when it is turned in a counter-clockwise direction the thermostat set ting is lowered.

The setting of the thermostat is shown by the indicator 4!), the end of which points to the indicia 4i mounted below the handle. The end of the indicator it appears through an arcuate opening 42 in the body of the iron. In the particular form shown, this opening also passes through the handle support i3. The indicia 4! are marked for the suitable settings, usually ranging from cotton at the left to rayon at the right. The indicator (it is operated synchronously with the setting of the thermostat it by means of a gear train t5 connected to the square sleeve 46 which is slidably mounted on the post l9 between the head 26 and the collar 21. A ring gear 4"! having a square central opening is slldably mounted on the sleeve 46 and meshes with the larger circumference of a flat ring reducing gear 48. The smaller circumference oi. the gear meshes with the toothed arcuate member 49 pivoted on the shaft 50 and bearing the indicator Ml.

It will thus be observed that as the knob i5 is turned in a counter-clockwise direction, as shown in Figures '1 and 4, the sleeve 46 is rotated in the same direction, carrying with it the ring gear 41 which rotates the reducing gear 48 in a clockwise direction and the arcuate member in a counterclockwise direction, thus moving the indicator 40 to the right. The ring gear 4! slides upon the sleeve 46 as the latter is raised or lowered and is held in engagement with the reducing gear 48 by the support 5| below it and by the hood i2 above it. It will also be noted that the indicator 40 may be calibrated with the thermostat I before the knob i is placed in position. Then, regardless of the relative position of the sleeve 46 with respect to the head 26, this relativeposition will be maintained at all times by anchoring of the corners of the sleeve and the head in the notches on the inside of the knob. V

The temperature indicator preferably comprises a thermostatic coil 60 secured to the sole plate of the iron in a central location, as shown in Figure 5. This coil may be of conventional bimetallic material and each end or the coil is sharply bent, the inner end 6| being bent inwardly, and the outer end being bent outwardly. The outer end 62 is slidably carried within a slot 64 in the post 65 secured to the sole. plate. The inner end 6| is slidably carried near'the base of the post 50. The base 86 of the post 50 is rotatably Journalied in the sole plate. As a result, when the temperature of the sole plate rises, the coil expands and turns the shaft 50 in a clockwise direction. The temperature indicating means 10 is secured to the neck of the shaft 50 and rotates therewith. This means comprises a ring II having its circumferential portion underlying the opening 42 and the point of the setting indicator 40. The ring H is painted appropriately, for example, with a red zone 12, a yellow zone 13, and a green zone 14, and is so calibrated that whenever the yellow zone underlies the setting indicator, the temperature of the iron is the temperature indicated by the setting indicator. On the other hand, when the red zone underlies the setting indicator, the temperature of the iron will be above that suitable for the particular operating conditions indicated, and when the green zone underlies the pointer, the temperature of the iron will be below that suitable for the preferred operating conditions. This calibration may be secured in any suitable way, either by applying the distinctive temperature indicia after testing of the iron, or by making the post 62 movable and adjusting it, or by mounting the ring II on the post 50 in such manner that it may be rotatably adjusted.

it will be observed that the operator has the knob immediately adjacent to the thumb or first and second fingers and may operate the knob while the iron is in ironing position or upright in rest position. At the same time the setting indicator is at the more rearward and lower part of the iron so that the hand does not hide it, nor is it necessary for the operator to peer around the front of the iron in order to discover the setting of the iron. Above all, the operator may see at a single glance whether the iron is 4 actually at the desired temperature setting, be cause unless the yellow zone on the ring II is immediately beneath the pointer 40, the iron is not at the right temperature. If the red zone shows, the iron is too hot; whereas, if the green zone shows, the iron is too cold.

The ability of the coil to slide within two sockets or slots assists materially in maintaining accuracy, and in avoiding twisting of the coil under stress. The necessary small adjustments to avoid twisting strains are made by sliding movement in the slots.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom.

What I claim as new and desire to secure by Letters Patent is:

1. In an electric sadiron having a sole plate, means for heating the sole plate, a hood above the sole plate forming with the sole plate a body portion, a handle, an adjustable thermostat, an adjustable setting indicator synchronized therewith and indicating the setting of the thermostat in terms of operating conditions of the iron and a temperature indicator, the setting indicator and the temperature indicator being in substantially vertically superposed relationship whereby the setting indicator and the temperature indicator are in visual alignment.

2. An iron as set forth in claim 1 in which the temperature indicator includes a horizontally movable element bearing temperature indications and the setting indicator includes a pointer overlying the temperature indications.

3. An iron as set forth in claim 1, in which the setting indicator and temperature indicator and thermostat are all within the body of the iron and the indicators-are visible through an opening in the body.

CHARLES H. SPARKLIN.

REFERENCES CITED The following references are of record in the Kuhn et al. Mar. 25, 1941 

